Do not trigger inefficient_to_string after Rust 1.82

[samueltardieu]

Starting with Rust version 1.82.0, the compiler generates similar code with and without the with_ref cfg:

fn f(x: impl IntoIterator<Item = String>) {
    for y in x { println!("{y}"); }
}

fn main() {
    #[cfg(with_ref)]
    let a = ["foo", "bar"].iter().map(|&s| s.to_string());
    #[cfg(not(with_ref))]
    let a = ["foo", "bar"].iter().map(|s| s.to_string());
    f(a);
}

The generated code is strictly identical with -O, and identical modulo
some minor reordering without.

changelog: [inefficient_to_string]: do not trigger for Rust ≥ 1.82.0

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[github-actions]

Lintcheck changes for 951d35e

Lint	Added	Removed	Changed
clippy::inefficient_to_string	0	5	0

This comment will be updated if you push new changes

[Jarcho]

This was fixed in 1.82. I wouldn't deprecate it, but MSRV gating it should be fine.

[samueltardieu]

Code, description, and title updated to not trigger the lint starting from Rust 1.82.0.

r? Jarcho since you suggested this

[Jarcho]

cc @rust-lang/clippy

I'll wait and see if anyone else has anything to say before merging. This is the opposite of how we use MSRV everywhere else, but it makes sense with how the lint is useless after a specific version.

[Jarcho]

Thank you.

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